Experts in the best position to observe, like catcher Jim Hegan of the world's champion Cleveland Indians, generally agree that speed and control are the biggest factors. The game's great have varied widely in size, shape and temperament, and many were famous for a particular kind of pitch, but every one had better-than-average speed and fine control.

Hegan knows how star hurlers perform. He catches a Cleveland staff that has been called the best ever assembled on one team. Two of its members, Bob Lemon and Gene Bearden, were 20-game winners last season. A third, Bobby Feller, with nearly 200 major-league victories and over 2000 strikeouts to his credit, ranks as one of baseball's all-time greats.

A government timing device clocked Feller's fast one at 99.5 miles an hour. Batters have a split second to decide whether or not to swing with the ball hurtling toward them from only 60 feet 6 inches away--the distance between the mound and home plate. But even with his natural speed, Feller couldn't climb to stardom until he mastered control.

Some pitchers laid the groundwork for good control as youngsters by throwing for hours at a time at stationary targets. Some would pitch stones or balls at a hole in the fence. Others have rigged up "picture frames" of canvas or poles, with a 17-inch-wide and 38 or 39-inch-high opening representing the strike zone for an average-size batter.

Reduced to its simplest explanation, pitching skill is the ability to throw consistently what the batter least expects or wants. Watching the pitchers work from Hegan's vantage point behind the plate, you get a better idea of the finesse that makes a champion.

Deceiving sharp-eyed big leaguers takes grade-A performance at all times. In their constant duel of wits, the pitcher can't afford to give the batter an inkling as to what kind of a pitch he'll serve up. Coaches and rival players are watching him constantly for telltale signs.

Unconscious mannerisms sometimes betray a rookie pitcher's intentions. George Earnshaw of the Philadelphia Athletics originally had a habit of scuffing ground around the mound with his toe when catchers flashed the curve sign, while the call for a fast ball brought no such response. Until corrected, it was like posting an announcement each time for the hitter.

Urban "Red" Faber of the Chicago White Sox, a famous spit-ball pitcher, would overdo preparations for the saliva-applying operation when he was faking his favorite delivery. Opponents noting the exaggerated facial contortions could be reasonably sure Faber's wicked "spitter" wasn't shortly coming their way.

Babe Ruth, in his youthful pitching days, would unconsciously stick out his tongue when preparing to throw a curve. Others have unknowingly tipped off rivals by hitching up their shoulders prior to a certain type pitch, or crooking their wrist significantly during the start of the windup.

Managers and coaches are always on the alert to detect and correct these faults in their players. Occasionally a cagey pitcher will use these "giveaways" to his own advantage in double crossing rivals. Dizzy Dean used to allow the opposition to "discover" his preliminaries for a certain type pitch, adding to its authenticity by using it a few times in the expected manner, then crossing them up at crucial moments by switching at the last minute to a completely different kind of pitch.

Coaches teach youngsters to deliver all pitches with the same motion, generally a three-quarter style, about midway between sidearm and overhand. Except for a few freak specialty pitches, the fingering--the way the ball is gripped--is basically the same for all pitches. A smart pitcher masks the fingering with his gloved hand.

For about 75 percent of all pitches, the forefinger and second finger are on top of the ball, the thumb is below it and the two remaining fingers fold down against the palm. Most experts advocate gripping the ball across the seams, rather than with them, to get better control.

A fast ball behaves differently from a curve because of the way the ball is released. There isn't time then for a batter to react to the knowledge, even if he had it.

Fast balls leave the hand with a downward snap of the wrist. A good, "live" pitch, in baseball parlance, shoots upward when it nears the batter. One that fails to rise and comes straight, level across the plate, is easy to hit, despite its speed, and it travels farther than breaking-type pitches.

Though held the same, a curve is thrown with an outward snap of the wrist so that the back of the pitcher's hand ends up facing the plate. The ball rolls off the first two fingers. Most effective curve-ballers put pressure on the second finger, just before the release, and use the first solely as a guide. The ball has to be made to spin in order to curve.

Some hurlers finger a slow ball, or "change up," just as they do a fast ball or curve, but lift the top two fingers just as the ball is released. When thrown with the same motion as a fast one--except for the last-second wrist snap--it throws a batter's timing off badly.

The sharpest change of pace in baseball today is the "blooper ball" thrown by Rip Sewell of Pittsburgh. It floats platewards so slowly that batters can see the ball's seams and it arches down to them from as high as 12 to 15 feet, but Rip uses it sparingly and hitters aren't able to adjust their timing for solid swings.

Among the most effective "extra" deliveries is the knuckler. Manager Lou Boudreau of Cleveland claims it is the most baffling ball his star Bearden throws. Gene grips it with the nails of his first three fingers and the sphere sails up to the plate with virtually no spin, breaking downward. Some knucklers, like Dutch Leonard of the Chicago Cubs, hold it with two fingers on top, pressing the first joints against the ball.

Carl Hubbell, the former New York Giant southpaw, perfected a screwball that he held just like a curve. The difference was in the terrific inward snap he gave the ball on release, ending up with his palm facing the batter. This spin made the ball act like a reverse curve.

Early Wynn, another Cleveland star, has a bothersome slider which he grips like a curve, but holds slightly off center, and throws with less wrist snap. It breaks several inches but, unlike the curve, it "slides" away from right-handed batters without also breaking downward.

Some of the more methodical hurlers keep notebooks in which they jot down the data on the batting strengths and weaknesses of rivals. When a hitter like Rudy York displays a liking for pitches that catch the outside edge of the plate, it is pretty certain he'll never get one there when the game is close.

Hurlers have equally long memories for weak points. Feller, who has been playing against Joe DiMaggio for 10 years, thinks the Yankee star normally does the least damage to a ball that breaks low, on the outside corner.

Catchers are important to pitchers in analyzing the batter's stance and swing. This is particularly true when a newcomer is at bat. If he is a plate crowder, the catcher will probably call for balls that break in close to his bat handle. Or, if he stands too far back, the catcher might ask for a curve or fast ball that nicks the corner.